He said the gunman, Adam Lanza, had significant mental health issues that affected his ability to live a normal life and interact with others but did not affect his mental state for the crimes.{ }

However, reports paint killer Adam Lanza as a 20-year-old who was bullied as a child and obsessed with mass killings – particularly with the 1999 shootings at Columbine High School.

A timeline shows that at 9:34 a.m., the first parent reported hearing gunfire. One minute later at 9:35 a.m., the first 911 call was made from the school’s nurse’s office.

Four minutes later, police arrived as gunfire could still be heard.

Then at 9:40 a.m., a single shot rang out in Room 10 at Sandy Hook Elementary School – which was Lanza taking his own life.

Weapons recovered include a Bushmaster Semiautomatic weapon and two automatic pistols; a 12-gauge shotgun was found in his car’s trunk, and a rifle that Lanza used to kill his mother that morning was found on her bedroom floor.

Lanza lived with his mother, and at their home, police found the windows of his bedroom and a computer room blacked out with trash bags. They also found clippings of other school shootings and photographs of dead humans. They also uncovered numerous violent video games.

The Dec. 14 shooting plunged the small New England community into mourning, elevated gun safety to the top of the agenda for President Barack Obama and led states across the country to re-evaluate laws on issues including school safety.

The report expected Monday afternoon will not include the full evidence file of Connecticut State Police, which is believed to total thousands of pages. The decision to continue withholding the bulk of the evidence is stirring new criticism of the secrecy surrounding the investigation.

Dan Klau, a Hartford attorney who specializes in First Amendment law, said the decision to release a summary report before the full evidence file is a reversal of standard practice and one of the most unusual elements of the investigation.

"What I found troubling about the approach of the state's attorney is that from my perspective, he seems to have forgotten his job is to represent the state of Connecticut," Klau said. "His conduct in many instances has seemed more akin to an attorney in private practice representing Sandy Hook families."

Sedensky said he could not comment.

Twenty-year-old Adam Lanza killed his mother inside their Newtown home before driving to his former elementary school, where he fired off 154 shots with a Bushmaster .223-caliber rifle within five minutes.

But authorities have not provided details on the police response to the shooting, any mental health records for Lanza and whether investigators found any clues to a possible motive for the rampage.

The State’s Attorney is opposed to their release, but a judge heard arguments on Monday on whether they should be heard, as the public considers the issue as well.

While some think they should be released and have it over with, others thing they should be kept private and the families left alone.

The withholding of 911 recordings, which are routinely released in other cases, has been the subject of a legal battle between The Associated Press and Sedensky before the state's Freedom of Information Commission, which ruled in favor of the AP, and now Connecticut's court system.